| Year | Value | | 2024 | 20,785,855 | | 2023 | 20,178,393 | | 2022 | 19,596,620 | | 2021 | 19,240,905 | | 2020 | 19,135,365 | | 2019 | 18,933,946 | | 2018 | 18,668,093 | | 2017 | 18,412,189 | | 2016 | 18,198,458 | | 2015 | 17,994,677 | | 2014 | 17,858,518 | | 2013 | 17,683,759 | | 2012 | 17,505,132 | | 2011 | 17,322,863 | | 2010 | 17,157,520 | | 2009 | 16,968,086 | | 2008 | 16,774,720 | | 2007 | 16,592,802 | | 2006 | 16,431,516 | | 2005 | 16,267,070 | | 2004 | 16,116,023 | | 2003 | 15,967,799 | | 2002 | 15,826,407 | | 2001 | 15,660,029 | | 2000 | 15,497,675 | | 1999 | 15,358,924 | | 1998 | 15,234,832 | | 1997 | 15,108,952 | | 1996 | 14,961,771 | | 1995 | 14,805,153 | | 1994 | 14,648,495 | | 1993 | 14,484,401 | | 1992 | 14,318,211 | | 1991 | 14,143,139 | | 1990 | 13,967,885 | | 1989 | 13,755,869 | | 1988 | 13,504,466 | | 1987 | 13,325,840 | | 1986 | 13,149,360 | | 1985 | 13,015,632 | | 1984 | 12,889,906 | | 1983 | 12,759,834 | | 1982 | 12,625,403 | | 1981 | 12,467,722 | | 1980 | 12,306,806 | | 1979 | 12,140,390 | | 1978 | 12,009,530 | | 1977 | 11,877,269 | | 1976 | 11,725,894 |
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